Insertion device for an insertion set and method of using the same

ABSTRACT

An insertion device and insertion set. The insertion device for inserting at least a portion of at least one piercing member of an insertion set through the skin of a patient includes a device housing, a carrier body and a driver. The carrier body is slidably received within the device housing for movement between an advanced position and a retracted position. The carrier body also includes a receiving structure to support the insertion set in a position with the at least one piercing member oriented for insertion through the skin of the patient at a predetermined angle relative to the skin of the patient upon movement of the carrier body from the retracted position to the advanced position. The driver is operatively coupled between the device housing and the carrier body to urge the carrier body with a controlled force and speed from the retracted position toward the advanced position to place at least a portion of the at least one piercing member of the insertion set thorough the skin of the patient to install the insertion set to the patient. The receiving structure of the carrier body is removable from the insertion set while maintaining the installation of the insertion set to the patient.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.09/839,052, filed Apr. 20, 2001, now U.S. Pat. No. 6,607,509 which is acontinuation-in-part of U.S. patent application Ser. No. 09/215,356,filed Dec. 18, 1998 (issued to Safabash et al. as U.S. Pat. No.6,293,925 on Sep. 25, 2001), which, in turn, is a continuation-in-partof U.S. patent application Ser. No. 09/002,303, filed Dec. 31, 1997(issued to Funderburk et al. as U.S. Pat. No. 6,093,172 on Jul. 25,2000), which, in turn, is a continuation-in-part of U.S. patentapplication Ser. No. 09/795,968, filed Feb. 5, 1997 (issued to Marano etal. as U.S. Pat. No. 5,851,197 on Dec. 22, 1998), the disclosures ofwhich are included or incorporated by reference in the presentapplication.

FIELD OF THE INVENTION

This invention relates generally to an insertion device for automaticplacement of an insertion set through the skin of a patient, and inparticular embodiments to a compact and easily operated insertion devicefor placement of an insertion needle of a subcutaneous insertion set orthe like through the skin of a patient with a controlled force andinsertion speed by the patient.

BACKGROUND OF THE INVENTION

Medical needles are widely used in the course of patient care andtreatment, particularly with respect to the delivery of selectedmedications to a patient. In one common form, hollow hypodermic needlesare employed for transcutaneous delivery of a selected medication from asyringe or the like. In another common form, insertion needles areemployed for transcutaneous placement of a soft and relatively flexibletubular cannula, followed by insertion needle removal and subsequentinfusion of medical fluid to the patient through the cannula. Morerecently, insertion needles have also been used for transcutaneouslyplacing other medical devices such as a subcutaneous sensor formonitoring specified patient parameters, such as blood glucose level.

In certain medical treatment regimens, it may be necessary or desirablefor the patient to transcutaneously place the medical needle. Forexample, diabetic patients frequently self- administer insulininjections or periodically place a subcutaneous insertion with a cannulafor subsequent programmable delivery of insulin by means of a medicationinfusion pump of the general type described in U.S. Pat. No. 4,685,903.Such subcutaneous insertion sets are disclosed, for example, in U.S.Pat. Nos. 4,755,173; 5,176,662; and 5,257,980 which are incorporated byreference herein. Diabetic patients may also use a subcutaneousinsertion set to periodically place a transcutaneous glucose sensorwherein such sensor insertion sets are disclosed, for example, In U.S.Pat. Nos. 5,390,674; 5,568,806; 5,586,553, which are also incorporatedby reference herein.

Some patients are reluctant or hesitant to pierce their own skin with amedical needle, and thus encounter difficulties in correct needleplacement for proper administration of the medication. Such difficultiescan be attributable to insufficient manual dexterity or skill to achieveproper needle placement or, alternately to, anxiety associated withanticipated discomfort as the needle pierces the skin. This problem canbe especially significant with medications delivered via a subcutaneousflexible insertion set, since incorrect placement can cause kinking ofthe cannula and resultant obstruction of medication flow to the patient.Cannula kinking can be due to insertion set placement at an incorrectangle relative to the patient's skin, and/or needle placement with anincorrect force and speed of insertion.

The present invention relates to an automatic injector, particularly foruse with a subcutaneous insertion set, for quickly and easily placing aninsertion needle through the skin of a patient at the correct insertionangle, and with a speed and force of insertion which minimizes patientdiscomfort.

SUMMARY OF THE DISCLOSURE

It is an object of an embodiment of the present invention to provide animproved insertion device and insertion set, which obviates forpractical purposes, the above mentioned limitations.

According to an embodiment of the invention, an injector is provided forquick and easy transcutaneous placement of a medical needle through theskin of a patient, particularly such as an insertion of a subcutaneousinsertion set. The injector is designed to place the needle through theskin at a selected insertion angle and with a controlled force and speedof insertion, to ensure proper needle placement with minimal patientdiscomfort. The injector is particularly designed to meet theseobjectives, while safeguarding against undesired projection of themedical needle through free space, in the event that the injector isactuated in spaced relation to the patient's skin.

The injector comprises a spring-loaded plunger having a head forreceiving and supporting an insertion set in a position with aninsertion projecting outwardly for transcutaneous placement through theskin of a patient. The plunger is designed for retraction and retentionwithin a barrel to a cocked position with a drive spring compressed in amanner applying a predetermined spring force to the plunger head. Afront or nose end of the injector barrel is designed for pressedplacement against the skin of a patient, at a selected needle insertionsite, and in an orientation with the needle disposed at a correct ordesired insertion angle. A trigger member is operable to release theplunger and thereby permit the drive spring to carry the insertion settoward the patient's skin with a controlled force and speed, resultingin proper transcutaneous placement of the insertion needle with minimalpatient discomfort.

The plunger head includes a safety lock mechanism to retain theinsertion set against projection from the injector barrel. In onepreferred form, the safety lock mechanism comprises at least one andpreferably a pair of safety lock arms for engaging and retaining theinsertion set when the plunger is retracted from a fully advancedposition. Each safety lock arm includes a cam lobe for engaging anappropriately shaped recess on the insertion set to prevent releasethereof from the plunger head, unless and until the plunger head isreturned to the fully advanced position. In such fully advancedposition, the shape of the cam lobe permits quick and easy separation ofthe injector from the insertion set with a minimal separation force.

In operation, the safety lock arms thus prevent projection of theinsertion set from the injector, in the event that the trigger member isactuated with the nose end of the barrel spaced from the skin of apatient. In that event, the plunger head is advanced with the controlledforce and speed to the filly advanced position, but the insertion set isnot thrown from the injector as a projectile. Instead, the insertion settravels rapidly with the plunger head to the fully advanced position,whereat the injector can be separated with minimal separation force fromthe insertion set.

In an alternative preferred form, the safety lock mechanism comprises aplunger head having a cylindrical shape defining a forwardly open cavityfor receiving and supporting an insertion set with the insertion needleand cannula projecting outwardly. In this embodiment, the plunger headincludes a radially inwardly projecting rim at a forward or nose endthereof, wherein the rim defines an oval-shaped opening. The size of therim opening permits relatively free reception of a hub on the insertionset, with the infusion set oriented at an angle relative to a centralaxis of the plunger head and barrel. The insertion set is thenreoriented to align the insertion needle coaxially with the central axisof the barrel and plunger head, so that the rim is received into arecess on the insertion set and functions to retain the infusion setagainst undesired release from the injector during spring-drivenplacement of the needle. After needle placement, the injector isreleased from the insertion set with minimal separation force byorienting the injector angularly relative to the insertion set to permitfree slide out passage of the hub through the oval rim opening.

In a further alternative form of the invention, the plunger head isshaped to define a laterally open undercut slot sized for relativelyfree slide-fit reception of the needle hub of the insertion set. In thisversion, the insertion set is assembled quickly and easily with theplunger head of the injector by laterally sliding the hub into thelaterally open slot, thereby orienting the medical needle generallycoaxially relative to the central axis of the injector barrel andplunger head. In this position, the plunger head can be retracted andlocked, followed by appropriate trigger member release fortranscutaneously placing the medical insertion needle. After the needleis placed on the patient, the injector can be disassembled from theinsertion set by laterally sliding the injector relative to the needlehub. Alternatively, the injector can be withdrawn or retracted from thepatient's skin to slidably separate the needle from the insertion setwhich remains in place on the patient's skin.

In other embodiments of the present invention, an insertion device forinserting at least a portion of at least one piercing member of aninsertion set through the skin of a patient includes a device housing, acarrier body and a driver. The carrier body is slidably received withinthe device housing for movement between an advanced position and aretracted position. The carrier body also includes a receiving structureto support the insertion set in a position with the at least onepiercing member oriented for insertion through the skin of the patientat a predetermined angle relative to the skin of the patient uponmovement of the carrier body from the retracted position to the advancedposition. The driver is operatively coupled between the device housingand the carrier body to urge the carrier body with a controlled forceand speed from the retracted position toward the advanced position toplace at least a portion of the at least one piercing member of theinsertion set thorough the skin of the patient to install the insertionset to the patient. The receiving structure of the carrier body isremovable from the insertion set while maintaining the installation ofthe insertion set to the patient.

In particular embodiments, the predetermined angle relative to the skinis about 90 degrees, between 90 degrees and 10 degrees, or is afterinsertion between 0 and 10 degrees. In additional embodiments, theinsertion set is a transuctaneous insertion set, a subcutaneousinsertion set, an infusion set, sensor set or the like. In still otherembodiments, the insertion set rests mainly on the surface of the skinafter insertion or the insertion set is implanted in the skin of thepatient. In preferred embodiments, the at least one piercing member is aneedle. In alternative embodiments, the at least one piercing member isa plurality of needles, and can also be a plurality of micro-needles.Also, in some embodiments, the insertion set insertion set can be bothan infusion set and a sensor set combined into an integral unit.

In yet other embodiments the insertion device, the device housing has aforward end defining a generally planar angled insertion contact surfacefor placement against the skin of a patient with the device housing in apredetermined orientation relative to the patient's skin that mirrorsthe predetermined angle relative to the skin of the patient. Otherembodiments include a trigger mechanism that actuates the driver. Forinstance, the trigger mechanism includes at least one trigger forfingertip depression to actuate the driver for movement of the carrierbody from the retracted position to the advanced position. In addition,the driver can include at least one spring for spring-loaded movement ofthe carrier body from the retracted position to the advanced position.Further, the driver can include a force changing mechanism that permitsalteration of the controlled force and speed of the carrier body movingfrom the retracted position to the advanced position from one insertioncycle to another insertion cycle. In still further embodiments, thedevice housing and the carrier body include a cooperatively engageabletrack mechanism for guiding movement of the carrier body between theadvanced and retracted positions while retaining the carrier bodyagainst rotation relative to the device housing.

In additional embodiments of the insertion device, the at least onepiercing member is provided with a piercing member hub as part of theinsertion set. In addition, the receiving structure of the carrier bodyincludes a recess formed therein for mated slide-fit reception of thepiercing member hub of the insertion set. Further, the recess of thereceiving structure can include a laterally open undercut recess.Alternatively, the receiving structure may include a safety retainerstructure that retains the at least one piercing member on the receivingstructure during movement from the retracted position to the advancedposition. This safety retainer structure permits separation of the atleast one piercing member from the carrier body when the carrier body isin the advanced position.

Yet another embodiment of the present invention is directed to aninsertion set for insertion through the skin of a patient by aninsertion device. The insertion device has a slidable carrier body formovement between an advanced position and a retracted position. Thecarrier body of the insertion device including a receiving structure tosupport the insertion set in a position for insertion through the skinof the patient upon movement of the carrier body from the retractedposition to the advanced position. The insertion device also having adriver operatively coupled to the carrier body that urges the carrierbody with a controlled force and speed from the retracted positiontoward the advanced position for insertion of the insertion set thoroughthe skin of the patient. The insertion set includes at least onepiercing member and a set housing. The at least one piercing memberincludes a portion of the at least one piercing member that isinsertable through the skin of the patient. The set housing is coupledto the at least one piercing member. Also, the set housing is shaped tofit within the carrier body of the insertion device to orient the atleast one piercing member for placement through the skin of the patientof at least a portion of the at least one piercing member at apredetermined angle relative to the skin of the patient to install theinsertion set to the patient. The set housing of the insertion set isremovable from the receiving structure of the carrier body whilemaintaining the installation of the insertion set to the patient.

In particular embodiments of the insertion set, the predetermined anglerelative to the skin is about 90 degrees, between 90 degrees and 10degrees, or is after insertion between 0 and 10 degrees. In additionalembodiments, the insertion set is a transuctaneous insertion set, asubcutaneous insertion set, an infusion set, sensor set or the like. Instill other embodiments, the insertion set rests mainly on the surfaceof the skin after insertion or the insertion set is implanted in theskin of the patient. In preferred embodiments, the at least one piercingmember is a needle. In alternative embodiments, the at least onepiercing member is a plurality of needles, and can also be a pluralityof micro-needles. Also, in some embodiments, the insertion set can beboth an infusion set and a sensor set combined into an integral unit.

Other features and advantages of the invention will become apparent fromthe following detailed description, taken in conjunction with theaccompanying drawings which illustrate, by way of example, variousfeatures of embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

A detailed description of embodiments of the invention will be made withreference to the accompanying drawings, wherein like numerals designatecorresponding parts in the several figures.

FIG. 1 is a perspective view illustrating use of an automatic injectorembodying the novel features of the invention;

FIG. 2 is an enlarged front elevation view of the injector shown in FIG.1;

FIG. 3 is a front or nose end view of the injector, taken generally onthe line 3-3 of FIG. 2;

FIG. 4 is an enlarged exploded perspective view illustrating assembly ofthe injector with a subcutaneous insertion set;

FIG. 5 is a further enlarged longitudinal sectional view taken generallyon the line 5-5 of FIG. 4;

FIG. 6 is a transverse sectional view taken generally on the line 6-6 ofFIG. 5;

FIG. 7 is an enlarged longitudinal sectional view taken generally on theline 7-7 of FIG. 2;

FIG. 8 is an enlarged and exploded fragmented perspective viewillustrating a trigger assembly for use in the injector;

FIG. 9 is a longitudinal sectional view similar to FIG. 5, and showingthe injector with insertion set received therein for transcutaneousplacement through the skin of a patient;

FIG. 10 is a transverse sectional view taken generally on the line 10-10of FIG. 9;

FIG. 11 is a longitudinal sectional view taken generally on the line11-11 of FIG. 9;

FIG. 12 is a rear end elevation view taken generally on the line 12-12of FIG. 11, and depicting the trigger assembly in a locked position;

FIG. 13 is an enlarged fragmented longitudinal view similar to a portionof FIG. 11, but depicting actuation of the trigger assembly forreleasing the spring-loaded plunger;

FIG. 14 is a rear end elevation view taken generally on the line 14-14of FIG. 13, similar to FIG. 12, but showing the trigger assembly in anunlocked position;

FIG. 15 is a fragmented longitudinal sectional view depicting thespring-loaded plunger in a fully advanced position with the infusion setplaced on the patient's skin;

FIG. 16 is an exploded perspective view illustrating separation of theinsertion needle from the cannula of the subcutaneous insertion set;

FIG. 17 is a perspective view depicting an alternative preferred form ofthe invention;

FIG. 18 is a front elevation view of the injector shown in FIG. 17;

FIG. 19 is a front or nose end view of the injector, taken generally onthe line 19-19 of FIG. 18;

FIG. 20 is an enlarged side elevation view of the injector, takengenerally on the line 20-20 of FIG. 19;

FIG. 21 is a further enlarged longitudinal sectional view takengenerally on the line 21-21 of FIG. 17;

FIG. 22 is an enlarged exploded perspective view illustratingconstruction details of a plunger and trigger member for use in theinjector of FIG. 17;

FIG. 23 is an enlarged longitudinal sectional view similar to FIG. 21,and depicting the injector with the trigger member in a cocked position;

FIG. 24 is a fragmented perspective view showing the upper end of theinjector depicted in FIG. 23, with the trigger member in the cockedposition;

FIG. 25 is an enlarged and fragmented longitudinal sectional viewillustrating actuation of the trigger member;

FIG. 26 is an enlarged and fragmented longitudinal sectional viewshowing the plunger in a fully advanced position with the infusion setplaced on the patient's skin;

FIG. 27 is an enlarged fragmented longitudinal sectional view takengenerally on the line 27-27 of FIG. 22, and depicting a portion of theplunger;

FIG. 28 is a front or nose end elevational view of the plunger, takengenerally on the line 28-28 of FIG. 27; and

FIG. 29 is an enlarged fragmented longitudinal sectional viewillustrating release of the injector from an infusion set placed on thepatient's skin;

FIG. 30 is an exploded prospective view generally similar to FIG. 17,but depicting a further alternative preferred form of the invention, andshowing assembly of an insertion set with the illustrative injector;

FIG. 31 is a perspective view similar to FIG. 32, depicting furtherassembly of the insertion set with the injector;

FIG. 32 is an enlarged fragmented vertical sectional view takengenerally on the line 32-32 of FIG. 31;

FIG. 33 is a perspective view showing use of the injector of FIGS. 30-32for transcutaneous placement of the insertion set; and

FIG. 34 is an exploded perspective view similar to FIG. 33, and showinguse of the injector to separate a medical needle from the installedinsertion set.

FIG. 35 is a perspective view of an insertion device with one type of aninsertion set in accordance with a second embodiment of the presentinvention.

FIG. 36 is a bottom perspective view of the insertion device of FIG. 35.

FIG. 37 is a side plan view of the insertion device and insertion setshown in FIG. 35.

FIG. 38 is an exploded cross-sectional view of the insertion device andthe one type of insertion set as shown along the line 38-38 in FIG. 37.

FIG. 39 is a top perspective view of one type of insertion set for usewith the insertion device shown in FIG. 35.

FIGS. 40 a-40 g illustrate the steps of inserting the one type ofinsertion set of FIG. 39 with the insertion device of FIG. 35.

FIG. 41 is a perspective view of an insertion device with one type of aninsertion set in accordance with a third embodiment of the presentinvention.

FIG. 42 is an exploded perspective view of the insertion device shown inFIG. 41.

FIG. 43 is an exploded side plan view of the insertion device and theone type of insertion set shown in FIG. 41.

FIG. 44 is an enlarged side plan view of the one type of insertion setheld in a carrier body of the insertion device shown in FIG. 41.

FIG. 45 is a front perspective view of the insertion device and the onetype of insertion set shown in FIG. 41.

FIG. 46 is a cross-sectional view of the insertion device and the onetype of insertion set as shown along the line 46-46 in FIG. 45.

FIG. 47 is a top schematic view of an insertion device in accordancewith a fourth embodiment of the present invention.

FIGS. 48 a-48 d are cross-sectional views of a force changing mechanismfor use with embodiments of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in the drawings for purposes of illustration, the invention isembodied in an insertion device for insertion sets such as an infusionset, sensor set, medical device, or the like. Further embodiments of theinsertion device may be used to insert other insertion sets or medicaldevices such as biodegradable implants, capsules, impregnated threads(with medications or the like). Other insertion sets may be directed toa threaded needle insertion set, such as that described in U.S. Pat. No.5,584,813 issued Dec. 17, 1996 to Livingston et al. entitled“Subcutaneous Injection Set” and U.S. Pat. No. 5,779,665 issued on Jul.14, 1998 to Mastrototaro et al. entitled “Transdermal IntroducerAssembly”, which are herein incorporated by reference. In addition, theinsertion sets may be coated with medications, or other agents, thatinhibit infection and/or promote healing of the insertion site.Preferred embodiments of the insertion device and insertion sets are fortranscutaneous placement of the insertion set in subcutaneous tissue.However, in alternative embodiments, the insertion set may be insertedinto other subdermal tissues. In addition, still further embodiments maybe used to place the sets in other types tissue, such as muscle, lymph,organ tissue or the like, and used in animal tissue. In preferredembodiments of the present invention, the insertion device is loadedwith a standard hand-held insertion set, or the like, and then placedagainst the skin of the user, where the insertion device is activated totranscutaneously place a portion of the insertion set, or the like,subcutaneously in a quick manner that minimizes pain and/or discomfortto the user. However, it will be recognized that further embodiments ofthe invention may be used to place an entire insertion set, or the like,beneath the skin, rather than just a portion of the insertion set. Asdiscussed, preferred embodiments of the insertion device are designed toaccommodate off-the-shelf insertion sets, or the like. But, alternativeembodiments may be used with customized insertion sets, or the like thathave been altered to fit the insertion device in a particularorientation or configuration to improve safety and/or assure properplacement of the insertion set, or the like. In still other embodiments,the insertion sets, or the like may be angled and the devices arecapable of insertion at angles between 0 and 90 degrees relative to theskin surface after insertion of the insertion set.

In preferred embodiments, the insertion set includes at least onepiercing member to pierce the skin during insertion. In particularembodiments, the piercing member is a metal needle. In alternativeembodiments, the needle may be hollow, solid, half needle (or otherfraction), or the like. In further alternative embodiments, the piercingmember may be made out of other materials, such as ceramic, plastic,composites, silicon micro-needles, biodegradable, hydrophillicsubstances, substances that soften and/or change once in contact withthe body and/or bodily fluids, or the like. In other alternativeembodiments, the insertion set may include more than one piercingmember. For example, a single insertion set may include a piercingmember for an infusion portion and another piercing member for aseparate sensor portion, or the like. Alternatively, the insertion setmay include a plurality of small piercing members on a small patch orsubstrate, such as a series of hollow micro-needles (such as fromsilicon, plastics, metal or the like) for infusion of a medication or aseries of solid micro-needles for sensor applications (such as fromsilicon, plastics, metal or the like), which micro-needles are used topenetrate the skin.

As shown in the exemplary drawings, an injector (or insertion device) inaccordance with a first embodiment of the present invention is referredto generally by the reference numeral 10 is provided for quick and easytranscutaneous placement of a medical needle, particularly such as aninsertion needle 12 of the type provided with a subcutaneous insertionset 14 as depicted in FIGS. 4 and 7. The injector 10 includes atrigger-type actuator mechanism for transcutaneous placement of theinsertion needle 12 with a controlled speed and force, and with theinsertion needle 12 oriented at a desired angular position relative tothe skin 16 (FIGS. 1 and 9) of the patient.

The automatic injector 10 of the present invention, as shown in theillustrative drawings, is particularly designed for placement of theinsertion needle 12 of a subcutaneous insertion set 14, such as aninsertion set of the general type shown and described in U.S. Pat. Nos.4,755,173; 5,176,662; and 5,257,980, which are incorporated by referenceherein. Such insertion sets 14 are used to infuse medical fluids such asselected medications to a patient, with one example being theadministration of insulin to a diabetic by operation of a programmablemedication infusion pump (not shown) of the type described in U.S. Pat.No. 4,685,903. Alternatively, the injector 10 may be used totranscutaneously place a medical needle associated with other types ofinsertion sets, such as transcutaneous sensor insertion sets of thegeneral type shown and described in U.S. Pat. Nos. 5,390,671; 5,560,806and 5,586,553, which are also incorporated by reference herein. Suchinsertion sets are used, for example, to monitoring patient glucoselevels.

As shown best in FIG. 4 with respect to an insertion set 14 for infusingmedical fluids to a patient, the insertion needle 12 is connected to ahub 18 at a rear or proximal end thereof, and protrudes through ahousing 20 of the insertion set 14, wherein the housing 20 defines aninternal chamber (not shown) for receiving medication via infusiontubing 22. An enlarged base, typically in the form of resilient orflexible wings 24, is provided on the housing 20 for stable affixationto the skin 16 of a patient. The insertion needle 12 protrudesdownwardly through the housing 20 and the winged base 24 to extendthrough a soft and flexible cannula 26. The insertion needle 12 isprovided for transcutaneous placement of the cannula 26, after which theinsertion needle is retracted from the set 14 (FIG. 16) to permitmedication delivery through the cannula 26 to the patient.

The injector 10 of the present invention represents a simple devicewhich can be used by the patient to quickly and easily place thesubcutaneous insertion set 14 in a proper transcutaneous position andorientation, at a selected medication insertion site. The injector 10 isdesigned to project the insertion set toward the patient's skin 16 at acontrolled force and speed for quickly piercing the skin in a mannerinsuring proper placement of the insertion needle 12 and cannula 26,while minimizing patient anxiety and/or discomfort. Improper and/orpartial placement of the insertion needle 12 is thus avoided.

In general terms, as shown in one preferred form is FIGS. 1-5, theinjector 10 comprises a cylindrical forward barrel 28 (or devicehousing) having a plunger 30 (or carrier body) mounted therein forlongitudinal sliding movement within a hollow bore between a forwardadvanced position (FIG. 5) and a rearward retracted position (FIG. 9).The plunger 30 has a head 32 at a forward end thereof for releasiblyreceiving and retaining the subcutaneous insertion set 14, in a mannerto be described in more detail. A rear end of the plunger 30 cooperateswith a trigger-type actuator assembly 34 mounted on the rear end of thebarrel 28. The trigger actuator assembly 34 (or driver) is adapted tohold the plunger 30 in a retracted position, against the force of acompressed drive spring 36. A trigger button 38 of the actuator assembly34 is adapted for fingertip depression to release the plunger 30 forspring-loaded travel toward the advanced position, and correspondingtranscutaneous placement of the insertion needle 12 through thepatient's skin.

FIGS. 2-5 illustrate construction details of the injector barrel 28,wherein the forward or nose end thereof defines a flat and generallyplanar surface for placement against the skin of a patient (FIG. 1) witha longitudinal axis of the barrel 28 oriented generally perpendicular tothe patient's skin 16. The barrel 28 has a size and shape forsubstantially mated sliding fit reception of the infusion set 14, withthe insertion needle 12 and related cannula 26 projecting in a directionfor placement on a patient. In this regard, the nose end of the barrel28 defines an opposed pair of relatively wide and open-ended cut outs 40for slide-fit reception of the oppositely projecting base wings 24. Anarrower slot 42 is also formed in the barrel nose end, at a locationfor slide-fit reception of the infusion tubing 22 attached to theinfusion set 14. Thus, the forward or nose end of the barrel 28accommodates sliding reception of the subcutaneous insertion set 14therein for movement along the cut outs 40 and the slot 42 between theadvanced position (FIG. 5) disposed substantially at the forwardmost endof the barrel 28, and the retracted position (FIG. 9) with the basewings 24 and infusion tubing 22 positioned substantially at the inboardends of the cut outs 40 and the associated slot 42.

The plunger 30 includes the head 32 of generally cylindrical shape forslide-fit reception within the injector barrel 28. A forward end of thehead 32 includes a cylindrical counterbore recess 44 for receiving thehub 18 and housing 20 of the insertion set 14, with the enlarged basewings 24 fitted against a pair of outwardly protruding backstop flanges46 adapted for slide-fit reception within the cut outs 40 in the barrelnose end. A pair of track arms 48 (FIG. 5) protrude rearwardly from theplunger head 32 and include out-turned latch fingers 50 for guidedreception within longitudinally extending track slots 52 formed in thebarrel 28 at a location spaced aft from the barrel nose end. These trackarms 48 thus cooperate with the barrel track slots 52 to guide theplunger 30 between the advanced position (FIGS. 5 and 7) and theretracted position (FIG. 9).

The plunger 30 also includes a central drive stem 54 (FIG. 5) whichprotrudes rearwardly from the plunger head 32 within the barrelinterior. The rearward end of the drive stem 54 is longitudinally splitto define a pair of trigger arms 56 which have out-turned triggerfingers 58 on 25 the rearward ends thereof.

The trigger-type actuator assembly 34 is mounted on the rearward end ofthe injector barrel 28, and generally functions to releasibly retain theplunger 30 in a retracted and cocked position, ready for rapid andspring-loaded actuation upon depression of the trigger button 38 toplace the insertion set 14 on the patient. More particularly, as shownbest in FIGS. 5-9, the trigger assembly 34 comprises a main support cap60 having a mounting sleeve 62 protruding in a press-fit and preferablyadhesively connected manner into the rear or aft end of the injectorbarrel 28. The drive spring 36 comprises a coil spring positioned aboutthe drive stem 54 on the plunger 30 and reacts between a rearward face64 of the plunger head 32, and a shoulder 66 on the support cap 60. Thedrive spring 36 normally biases the plunger 30 toward the advancedposition (FIGS. 5 and 7). However, an insertion set 14 seated in theplunger head 32 can be pressed rearwardly against the plunger 30 to movethe plunger to the retracted position, as viewed in FIG. 9, with thetrigger fingers 58 passed through a conical or tapered latch bore 68formed in the support cap 60 to engaging a shoulder 70 on an oppositeside of the support cap 60. In this regard, the trigger fingers 58 haveramped outboard faces to accommodate movement of the fingers 58 radiallytoward each other as they pass through the latch bore 68. When thetrigger fingers 58 pass entirely through the bore 68, the springresilience of the trigger arms 56 is sufficient to spread the triggerfingers 58 so that they engage the shoulder 70. In this retractedplunger position, the drive spring 36 is retained in a compressed andcocked condition, with the insertion set 14 including the insertionneedle 12 and related cannula 26 withdrawn into the interior of thebarrel 28, in spaced relation to the patient's skin 16.

The trigger actuator assembly 34 additionally includes an actuator pin72 mounted within a noncircular bore 74 (FIGS. 6 and 7) formed in thesupport cap 60 for longitudinal sliding movement through a short stroke,relative to the plunger 30. In this regard, the actuator pin 72 includesone or more noncircular lands 76 for slide-fit reception within the bore74, to prevent actuator pin rotation therein. The actuator pin 72 isheld within the bore 74 by a stepped lock ring 78 which is retainedagainst a rearward end of the support cap 60 by a press-fit outerretainer sleeve 80 having an inturned rim 82 at the rearward end thereofImportantly, as shown best in FIG. 8, an oblong land 84 is formed on theactuator pin 72 for mated slide-fit reception through an oblong recess85 formed in the lock ring 78. A return spring 86 (FIG. 7) is carriedwithin the support cap bore 74 and reacts between the shoulder 70 and anose end of the actuator pin 80 for biasing the actuator pin 80rearwardly within the support cap.

The rearmost end of the actuator pin 72 defines the trigger button 38.As shown in FIGS. 11 and 13, the trigger button 38 can be depressed witha fingertip to move the actuator pin 72 through a short stroke againstthe return spring 86 in a direction toward the trigger fingers 58 at therear end of the plunger 30. As shown best in FIG. 13, the actuator pin72 has a hollowed cylindrical forward tip 88 with a diametric size forengaging and squeezing the trigger fingers 58 together at the rear endof the plunger 30, in a manner enabling those trigger fingers 58 to passback through the tapered conical latch bore 68. As soon as the triggerfingers 58 thus release from engagement with the shoulder 70 on thesupport cap 60, the drive spring 36 translates the plunger 30 with theinsertion set 14 thereon with a rapid and controlled force and speedtoward the advanced position, resulting in transcutaneous placement ofthe needle 12 and cannula 26, as viewed in FIG. 15. Importantly, thespring rate characteristics of the drive spring 36 and the distance ofplunger stroke are chosen for a substantially optimized and propertranscutaneous placement of the needle 12 and cannula 26, all in amanner which minimizes patient discomfort during the needle placementprocedure. Moreover, by forming the nose end of the injector barrel 28with a squared-off shape as shown, the injector 10 can be easilyoriented substantially perpendicular to the skin 16 for proper placementof the insertion set.

Depression of the actuator pin 72 by means of the trigger button 38requires the lock ring 78 to be rotatably oriented in a positionaligning the oblong recess 85 therein with the oblong land 84 on theactuator pin. Accordingly, when these oblong structures are rotationallyaligned (FIGS. 13-14), the injector 10 is armed for trigger buttondepression and corresponding release of the retracted and cockedplunger. However, the lock ring 78 can be rotated relative to theactuator pin 72 to misalign these oblong structures, as shown in FIGS.9-12, whereupon the actuator pin 72 is locked in a rearward positionagainst depression and actuation. A set pin 90 on the lock ring 78 maybe provided and received within an accurate notch 92 formed in theretainer sleeve flange rim 82, to permit lock ring rotationback-and-forth through a part circle increment, on the order of about 90degrees. Appropriate indicia may be applied to the retainer sleeve rim82, such as the letter “L” for “locked” and the letter “A” for “armed”,as viewed in FIGS. 12 and 14, to provide a visual indication of thesetting of the trigger assembly 34.

In accordance with one aspect of the invention, the plunger head 32additionally includes a safety lock mechanism in the form of a pair ofsafety lock arms 94 pivotally carried in narrow slots 96 formed in theplunger head 32. These safety lock arms 94 have rearward ends connectedto the head 30 by pivot pins 98, and forward ends defining contouredlock fingers 100 which protrude into the plunger head recess 44. Asshown in FIG. 7, the safety lock arms 94 and their associated lockfingers 100 have a size and shape so that the fingers 100 can engage andretain the hub 18 of the insertion set 14, for example, by fitting intoa recess 101 defined between the hub 18 and housing 20 of the insertionset. Importantly, the locations of the lock arm pivot points are chosento insure that the lock arms 94 engage and retain the insertion set 14whenever the plunger 30 is moved from the advanced position (FIG. 7)toward and to the retracted position (FIG. 9). When the plunger 30reaches the fully advanced position, the safety lock arms 94 includingtheir respective pivot pins 98 are disposed within the wide cut outs 40and are therefore free to swing outwardly, relative to the insertion set14, to accommodate separation of the insertion set from the injector 10with a substantially minimum separation force. This configuration hasbeen found to be highly effective as a safeguard to prevent theinsertion set 14 from being thrown as a projectile from the injector 10,in the event that the trigger assembly 34 is activated without priorplacement of the injector 10 firmly against the patient's skin 16. Inuse, the subcutaneous insertion set 14 can be placed quickly and easilyinto the open nose end of the injector barrel 28, within the recess 44formed in the plunger head 32. Such assembly of the insertion set 14with the injector 10 requires simple alignment of the base wings 24 andinfusion tubing 22 with the appropriate cut outs and slots 40, 42 formedin the nose end of the barrel 28. The insertion set 14 and plunger 30can then be manually retracted rearwardly, against the drive spring 36,to the retracted position with the plunger 30 cocked and latched asviewed in FIGS. 9 and 11. The injector 10 can then be placed firmlyagainst the patient's skin 16, with the insertion set 14 supported inthe proper orientation and at a predetermined distance from the skin 16.Simple depression of the trigger button 38 releases the cocked plunger30 for spring-loaded travel rapidly albeit with a controlled speed andforce of insertion, to ensure penetration of the patient's skin withminimal discomfort, and in a manner which properly places the insertionneedle and cannula. The safety lock arms 94 prevent accidentalprojection of the insertion set 14 through free space, in the event thatthe trigger button 38 is prematurely depressed. When the insertion set14 is properly placed, however, the safety lock arms 94 release from theinsertion set with minimal force, for easy separation of the injector 10from the insertion set 14.

In preferred embodiments, the controlled speed and force of theinsertion device is obtained by selecting a spring constant of a springto propel and insert the insertion set at the proper speed and force toensure penetration with minimal discomfort. In alternative embodiments,as shown in FIGS. 48 a-48 d, there is the need to vary the speed andforce, from one insertion cycle to the next, to accommodate differentinsertion sets (such as finer needles, sensor sets fragility or thelike) and insertion site conditions (such as overweight, underweight,children or the like). As shown in FIG. 48 a, a force changing mechanism1000 having a spring 1002 enclosed in a sealed compartment 1004 is usedwith a set (or adjustable) orifice 1006 to allow equalization ofinternal and ambient pressures during the insertion stroke of theinsertion device. The sealed compartment 1004 includes sealing O-rings1008 and 1010 to seal the sealed compartment 1004. The O-ring 1008 sealsthe insertion set carrier body 1012, and the O-ring 1010 seals theactuator housing 1014 (which contains the orifice 1006) of the forcegenerating mechanism 1000. The force changing mechanism 1000 may beactivated by, for example, a trigger 1016 that is biased by a spring1018 to close off the orifice 1006 until depressed. The limiting flowthrough the office 1006 acts as a dampening force, counteracting thespring force from the spring 1002, thereby allowing control of insertionspeed and force. The orifice size can be adjustably attained through anumber of approaches, such as bearing 1020 and spring 1022 that blocksthe orifice 1006 and resists air flow based on the tension of the spring1022 on the bearing 1020 (see FIG. 48 b); while presenting a lowerresistance during retraction as the air contained in the sealedcompartment 1004 is compressed, forcing bearing 1020 against spring 1022to unseat the bearing 1022 from the orifice 1006 to present the maximumorifice size for escaping air during compression of spring 1002. Thisstructure minimizes the force needed to compress spring 1022 by allowingair in the sealed compartment 1004 to escape freely and quickly throughthe orifice 1006; rather than be compressed within the sealedcompartment 1004 because the orifice 1006 is restricted by bearing 1002.In another alternative, as shown in FIG. 48 c, a disk 1024 has aplurality of various sized holes 1026(1) to 1026(n). The disk 1024 isrotateable over the orifice 1006 to sequentially obstruct, completelyobstruct or partially obstruct the orifice 1006 flow path and changesthe effective size of the orifice 1006 by blocking the orifice 1006 withthe various sized holes 1026(1) through 1026(n). In another embodiment,as shown in FIG. 48 d, a tapered valve plug 1028 is threaded intoposition relative to the orifice 1006 to change the effective size ofthe orifice 1006. Other orifice 1006 size changing methods may be used.In addition, other methods of controlling the insertion speed and forcemay be used, such as controlled friction, change in spring tension,hydraulics, pneumatics or the like may be used.

Following separation of the injector 10 from the placed insertion set14, the insertion needle 12 can be withdrawn quickly and easily from thecannula as viewed in FIG. 16. Thereafter, the insertion set 14 can beused in a normal manner to deliver a selected medication through theinfusion tubing 22 and cannula 26 to the patient.

An alternative preferred form of the invention is shown in FIGS. 17-29,wherein components corresponding in structure and function to thosedescribed previously with respect to FIGS. 1-16 are identified by commonreference numerals increased by 100. The embodiment of FIGS. 17-29 showa modified injector 110 constructed from a reduced number of parts andincluding an alternative safety lock mechanism for preventing undesiredprojection of the insertion set 14 through free space in the event ofinjector operation without placing the nose end thereof firmly againstthe skin 16 of a patient. However, the alternative safety lock mechanismagain permits quick and easy separation of the injector 110 from theinsertion set 14, with minimal separation force. Once again, although aninsertion set for infusing medical fluids to a patient will be shown anddescribed, it will be understood that alternative insertion sets such astranscutancous sensor insertion sets and the like as previouslyreferenced herein may be used with the injector 110.

In general, the modified injector 110 comprises a plunger 130 and atrigger-type actuator 134 assembled with a generally cylindrical hollowbarrel 128. The plunger 130 has a generally cylindrical plunger head 132which defines a counterbore recess 144 for receiving and retaining thehub 18 of the infusion set 14. As shown best in FIGS. 27-29, a radiallyinwardly projecting rim 202 is formed on the plunger head 132 generallyat a leading or nose end of the recess 144, wherein this rim 202 has anoncircular and preferably oval or elliptical shape (FIG. 28) toaccommodate reception of the hub 18 into the recess 144 provided thatthe hub 18 is oriented angularly relative to a central longitudinal axisof the plunger 130 and barrel 128. Similar angular orientation of thesecomponents accommodates quick and easy separation thereof. However, whenthe insertion set 14 is oriented with the medical needle 12 alignedcoaxially with the barrel center axis, a portion of the rim 202 projectsinto the insertion set recess 101 to prevent release of the insertionset 14 from the injector 110.

More specifically, with reference to FIGS. 17-20, the barrel 128 againhas a forward or nose end defining a flat and generally planar surfacefor firm placement against the skin of a patient. The nose end of thebarrel 128 has a pair of relatively wide and generally opposed cut outs140 formed therein for slide-fit reception of the base wings 24 of theinsertion set 14, in combination with a narrower slot 142 for slide-fitreception of the infusion tubing 22. This slot 142 may be formed in oneor both sides of the barrel nose end.

The plunger 130 is slidably fitted into the barrel 128 for movementbetween an advanced position shown in FIGS. 17, 18, 20 and 21, and aretracted position shown in FIG. 23. The plunger 130 includes themodified plunger head 132 of generally cylindrical shape, formedpreferably to include a shallow notch or groove 133 in one side thereoffor slide-fit reception of the infusion tubing 22 on the insertion set14. In this regard, the plunger head groove 133 is formed in a positionaligned with the narrow slot 142 in the nose end of the barrel.

The plunger head 132 is formed integrally with a drive stem 154 whichprojects rearwardly within the barrel interior. As shown best in FIG.22, the drive stem 154 is flanked by and formed integrally with a pairof rearwardly projecting track arms 148 which have latch fingers 150formed at the rear ends thereof. As shown in FIGS. 21 and 23, theselatch fingers 150 are received slidably within longitudinally extendingtrack slots 152 formed in the barrel 128, and function to guide theplunger 130 between the advanced and retracted positions. Cushioningmaterial (not shown) may be included at the leading ends of the trackslots 152 to form a combined stop upon spring driver advancing motion ofthe plunger 130, as will be described.

The plunger 130 additionally includes a pair of trigger arms 156 whichproject generally rearwardly from a rear end of the drive stem 154 andhave out-turned trigger fingers 158 at the rear ends thereof (FIG. 22).These trigger fingers 158 are adapted and sized for partial radialcompression toward each other as they ride within the barrel base whenthe plunger 130 is displaced from the advanced position (FIG. 21) to theretracted position (FIG. 23). As the retracted position is reached, thetrigger fingers 158 are spring-loaded by the resiliency of the triggerarms 156 to move outwardly for partial reception into relatively shorttrigger slots 159 formed in the barrel 128. In this position, as shownin FIG. 23, the triggers fingers 158 retain the plunger 130 in theretracted position.

A drive spring 136 is mounted within the barrel 128 to react between thetrigger-type actuator 134 and the plunger 130, in the same manner aspreviously described with respect to FIGS. 1-16. In this regard, thetrigger actuator 134 comprises a generally cylindrical actuator sleeve188 mounted slidably within the barrel 128 at the rear or upper endthereof This actuator sleeve 188 has a tapered or ramped leading edgeface 188′ (FIGS. 22, 23 and 25) for engaging matingly shaped rampedouter faces of the trigger fingers 158, to radially compress the triggerarms 156 and release the plunger 130 for spring-loaded travel from theretracted and cocked position to the advanced position. A trigger button138 is formed integrally with the actuator sleeve 188 and is exposed forfingertip depression at the rear or top of the barrel 128 to move theactuator sleeve 188 into releasing engagement with the trigger fingers158.

As shown best in FIGS. 22 and 24-26, the triggers button 138 extendsthrough an opening formed in the rear of the barrel 128, generallywithin a lock sleeve 178 formed integrally with the barrel 128. The locksleeve 178 defines an oppositely formed pair of guide slots 192 foraligned reception of a pair of outwardly radiating lock tabs 184 formedon the trigger button 138. When the tabs 184 and rotationally alignedwith the guide slots -192, the trigger button 138 can be depressed toactuate the spring-locked plunger, as described. However, the lock tabs184 have sufficient length to permit fingertip rotation of the actuator134 to re-position the tabs 184 within shallow lock grooves 193 formedadjacent the guide slots 192. When the tabs 184 are seated in the lockgrooves 193, the lock sleeve 178 blocks depression of the triggersbutton 138 and thereby locks the injector 110 against actuation. Returnrotation of the actuation 134 to re-align the tabs 184 with the guideslots 192 is required before the injector can be activated.

In accordance with one aspect of the invention, the plunger head 132includes the safety lock mechanism in the form of the noncircular rim202 at the leading end of the recess 144 in the plunger head. As shownin FIGS. 27 and 28, the rim 202 has a generally elliptical shapedefining a major axis that is greater than the diameter of the hub 18 onthe insertion set 14, and a minor axis that is less than the hubdiameter. With this geometry, and by providing sufficient axial depth tothe plunger head recess 144, the hub 18 can be fitted into the plungerhead by angularly orienting the components to permit slide-fit of thehub 18 through the major axis portion of the rim 202. Subsequentre-orientation of the components to align the medical needle 12generally coaxially with plunger head 32 enables the minor axis portionof the rim 202 to project into the insertion set recess 101, therebylocking the components together. Thereafter, when the insertion set 14is placed on the patient (FIG. 29), the components are easily separatedby lifting the injector 110 off the insertion set 14 at the same angleto allow the hub 18 to press freely through the major axis center of therim 202. Importantly, such engagement and disengagement of thecomponents occurs with essentially no resistance force to separation.The infusion set 14 can be oriented angularly relative to the plunger130 only when the plunger is in the advanced position, with the adjacentbarrel 128 precluding such angular orientation when the plunger 130 ismoved rearwardly from the restricted position.

In an alternative mode of operation, subsequent to actuation of theinjector 110 to place the insertion set 14 of the patient, the injector110 can be simply withdrawn or retracted in a direction away from thepatient's skin 16, in which case the rim 202 at the nose end of theplunger head 132 will engage the needle hub 18 and thereby gentlywithdraw the medical needle 12 from the insertion set 14, In thismanner, the needle 12 is retracted from the cannula 26 which remains atthe desired transcutaneous insertion site.

A further alternative preferred form of the invention is shown in FIGS.30-34, wherein a further modified injector 210 is constructed andoperated generally as shown and described in FIGS. 17-29, but wherein analternative configuration for a plunger head 232 is provided. FIGS.30-32 show the injector 210 with the plunger head 232 in the advancedposition within the front or nose end of the barrel 128 which includesthe wide cut outs 140 and the narrow slot 142 for respective slide-fitreception of the base wings 24 and the tubing 22 of the insertion set14. As shown, the modified plunger head 232 has a laterally open recess244 formed therein of undercut geometry and laterally exposed throughthe cut outs 140 when the plunger is in the advanced position. Theinsertion set 14 can be slide-fit assembled with the plunger head 232,by fitting the hub 18 into the wider upper region of the recess 144,with an inturned rim 302 at the leading end of the plunger head fittinginto the insertion set recess 101. A laterally open gap 303 (FIG. 34) inthe rim 302 permits slide-fit reception of the hub 18 into the recess244, and a short carrier post 304 (FIG. 32) may be provided at the baseof the recess 244 to seat within a shallow detent in the top of the hub.

With the insertion set 14 assembled with the plunger head 232, as viewedin FIG. 32, the plunger can be retracted and cocked as previously shownand described with respect to FIGS. 17-29. The cut outs 140 and slot 142accommodate sliding movement of the insertion set 14 with the plunger232 during such retraction. Thereafter, the front or nose end of theinjector 210 can be placed firmly against the patient's skin (FIG. 33)and the trigger button 138 depressed to release the plunger so that themedical needle 12 is transcutaneously placed with the controlled driveforce and speed. During forward drive motion of the plunger, the forwardrim 302 on the plunger head 232 prevents projectile release of theinsertion set. After placement of the insertion set on the patient, theinjector 210 can be laterally displaced relative to the insertion setfor quick and easy separation therefrom. Alternately, as viewed in FIG.34, the injector 210 can be withdrawn or retracted from the insertionset 14 to slidably withdraw the medical needle 12 while leaving theinsertion set in place on the patient.

FIGS. 35-40 g illustrate an insertion device 500 in accordance with asecond embodiment of the present invention. The insertion device 500includes a barrel 502 (or device housing) having a surface seat 501 andan assembly port 503, a carrier body 504 (or plunger or the like) havingan assembly rim 505 and a seating flange 506, a drive spring 507 (ordriver), a release button 508, and dual spring triggers 510 and 512. Asshown in FIG. 35, the barrel 502 performs as a housing to hold thecarrier body 504. The carrier body 504 is connected to the barrel 502 bythe carrier body being inserted through an opening in the surface seat501 of the barrel 502, and then passing the assembly rim 505 of thecarrier body 504 through the assembly port 503 of the barrel 502. Thesection of the carrier body 504 with the assembly rim 505 compressesslightly, as it passes through the assembly port 503, due to thepresence of compression slots 509, and then essentially restores to itsoriginal shape to prevent the carrier body 504 from sliding out of thebarrel 502, since the assembly rim 505 of the carrier body engages withthe assembly port 503 of the barrel 502.

The carrier body 504 is driven to an advanced position from a retractedposition by the drive spring 507 and held in the retracted position (orreleased to move to the advanced position) by the trigger buttons 510and 512. This embodiment of the insertion device 500 is primarilyadapted for insertion of insertion sets 400 (as exemplary shown in FIG.39 as an infusion set), or the like, that are inserted with the piercingmember 402 (or needle) at 90 degrees (or perpendicular) to the skinsurface after insertion. In preferred embodiments, the carrier body 504is permanently coupled to the barrel 502 and new insertion sets 400 areattached to the carrier body 504 for each new insertion. However, inalternative embodiments, the carrier body 504 may be a disposable thatis replaced after each insertion so that, for instance, a carrier body504 may be shipped with a pre-installed insertion set 400 and thenloaded into the barrel 502 of the insertion device 500.

The insertion device 500 features a low profile compact package thattends to minimize the effects of hand movement during insertion of theinsertion set 400. In this embodiment, the release button 508 isdepressed to release the insertion set 400, or the like, from thecarrier body 504 of the insertion device 500; rather than engaging ordisengaging the insertion set 14 using a lateral slot as shown in FIGS.31-34 above. The release button 508 can be used before or afterinsertion of the insertion set 400, or the like. To facilitate insertionof an insertion set 400, or the like, the insertion device 500 utilizesdual trigger buttons 510 and 512, which provide an extra margin ofsafety and substantially prevents accidental activation of the insertiondevice 500 upon contact with the skin surface. This obviates the needfor a lock and unlock position on the activation buttons (or triggers)of the earlier insertion devices shown in FIGS. 1-34. The insertiondevice 500 also includes another rim on the carrier body 504 that formsthe seating flange 506 to hold a rim 404 (or wing) of the insertion set400, or the like, that carries an adhesive 406 for adhering theinsertion set 400 to the surface of the skin. Upon activation of theinsertion device 500 to move the carrier body to the advanced position,the seating flange 506 presses the adhesive 406 and rim 404 of theinsertion set 400 firmly against the skin surface to provide positiveseating and attachment of the insertion set 400 to the skin. This maymake it unnecessary to require placement of an additional adhesive patchprior to or after inserting an insertion set 400 to secure the insertionset 400 at the insertion site. The insertion device 500 further includesan automatic release of the piercing member (or needle) hub 408 andpiercing member 402 (or needle) from the insertion set 400, or the like,after the insertion set 400, or the like, has been inserted. Thispermits the insertion set 400 to be left on the skin surface without thepiercing member hub 408 and piercing member 402 (or needle) remaining bysimply removing the insertion device 500 from the skin surface. Thisautomatic release feature also minimizes potential patient contact withthe piercing member 402 (or needle) of the insertion set 400, or thelike.

In preferred embodiments, the insertion set 400, or the like, is adaptedto tightly fit within a cavity 514 (or receiving structure) of thecarrier body 504. The cavity 514 of the carrier body 504 includes guides516 to orient the insertion set in a particular orientation and anexpansion member 518 in the center bottom interior of the cavity 514 ofthe carrier body 504 to engage with the piercing member hub 408 (orneedle hub) of the insertion set 400, or the like. The piercing memberhub 408 of the insertion set 400, or the like, includes a center section410 that engages with the expansion member 518 with a slightinterference fit. The interference fit expands the center-section 410 ofthe piercing member hub 408 slightly to expand and press the piercingmember hub 408 against the sides of the cavity 514 of the carrier body504 to firmly secure the insertion set 400, or the like, within thecavity 514 of the carrier body 504. The tight fit of the insertion set400,or the like, in the carrier body 504 substantially prevents theinsertion set 400, or the like, from being dislodged when the insertiondevice 500 is activated to improve insertion of the insertion set 400,or the like, on the skin. However, the tight fit also prevents theinsertion set 400, or the like, from being ejected if the insertiondevice 500 is inadvertently activated When it is not pressed against theskin surface. In preferred embodiments, the insertion device 500 isconfigured to have guides 516 and an expansion member 518 to work withexisting insertion sets 400, or the like. However, in alternativeembodiments, the insertion set 400, or the like, may be modified to havea piercing member base, housing or the like that includes slots (notshown) for receiving guides and expanding members of the insertiondevice 500 to improve the connection between the insertion device 500and the insertion set 400, or the like. In further alternativeembodiments, the guides and expansion members may be formed on theinsertion set 400, or the like, and the corresponding guide slots andexpanding sections may be formed on the insertion device 500.

The illustrated embodiment employs a dual trigger activation structureto minimize the ability of the insertion device 500 to beunintentionally activated. As illustrated, the barrel 502 of theinsertion device 500 includes two outwardly extending guide channels 520and 522 on the side of the barrel 502. The guide channels 520 and 522extend from the base 524 of the barrel 502 up to portal openings 526 and528 in the side of the barrel 502. The dual trigger buttons 510 and 512are carried on opposite sides of the seating flange 506 at the end ofthe carrier body 504. Each trigger button 510 and 512 is biased outwardfrom the side of the seating flange 506 by a trigger spring 530 and 532between the end of the trigger buttons 510 and 512 and the side of theseating flange 506. When the carrier body 504 of the insertion device500 is locked in the firing position (or retracted position), thetrigger buttons 510 and 512 are pushed out by the trigger springs 530and 532 to extend out of the portal openings 526 and 528. In thisposition, the trigger buttons 510 and 512 extend beyond the bottom ofthe guide channels 520 and 522, which prevents the trigger buttons 510and 512 from moving down the guide channels 520 and 522. To activate theinsertion device 500, the user must depress both trigger buttons 510 and512 so that the trigger buttons 510 and 512 can then slide along thebottom of the guide channels 520 and 522, which in turn allows thecarrier body 504 to move down along the barrel 502 until the insertionset 400, or the like, is inserted. In preferred embodiments, the portalopenings 526 and 528 and the end of the guide channels 520 and 522terminating at the portal openings 526 and 528 are rounded to match theshape of the trigger buttons 510 and 512. This tends to minimize theresisting pressure on the trigger buttons 510 and 512 during depressionof the trigger buttons 510 and 512. However, in alternative embodimentsother portal opening and guide channel end shapes, such as beveled,squared, polygonal, or the like, may be used.

The end of the carrier body 504 having the assembly rim 505 is connectedto a release button 508 that can be depressed or slightly extendedrelative to the carrier body 504. The release button 508 includesengagement tabs 550 and lock teeth 552 (see FIGS. 35 and 36) that engagewith carrier slots 554 and carrier locks 556 (see FIGS. 36 and 38) tolock the release button 508 to the carrier body 504. The lock teeth 552engage with the carrier locks 556 (see FIGS. 36 and 38) to permit anamount of movement of the lock teeth 552 along the carrier locks 556 toallow the release button 508 to be depressed to release an insertion setfrom the carrier body 504. The release button 508 is also slightlyextended away from the carrier body 504 when an insertion set 400 isplaced in the interior cavity 514 of the carrier body 504 to permitseating of the insertion set 400. Engaging the release button 508 withthe carrier body substantially prevents the compression slots 509 andassembly rim 505 from compression and inhibits release of the carrierbody 504 from the barrel 502 of the insertion device 500.

The release button 508 is depressed to release the insertion set 400, orthe like, from the carrier body 504 of the insertion device 500. Therelease button 508 pushes the insertion set 400, or the like, out of thecavity 514 of the carrier body 504 sufficiently enough to release theinsertion set 400, or the like, from the guides 516 and the expandingmember 518 in the cavity 514 and leave the inserted insertion set 400,or the like, on the skin. Alternatively, the release button 508 may beactivated to release an insertion set 400, or the like, from the carrierbody 504 prior to the insertion set 400, or the like, being inserted bythe insertion device 500. The release button 508 also includes a rampportion 534 (or other trigger mechanism) that is adapted to bend oradjust the piercing member hub 408 (or needle hub) of the insertion set400, or the like, to allow the piercing member hub 408 and piercingmember 402 (or needle) to be released and separated from the insertionset 400, or the like, when the insertion set 400, or the like, has beeninserted and the insertion device 500 is lifted off the skin. This canbe accomplished by separating the elements of the insertion set 400, orthe like, so that only the insertion set, or the like, housing andtubing (or wiring or the like) are left in contact with the skin. Theability to remove the piercing member hub 408 and piercing member 402 ispreferably facilitated by the adhesive 406 of the insertion set 400, orthe like, that attaches to the skin to provide sufficient tension toallow for separation of the piercing member hub 408 and the piercingmember 402 from the rest of the insertion set 400, or the like, withoutdislodging the insertion set 400, or the like. In preferred embodiments,the insertion device 500 is adapted to work with an existing piercingmember hub 408 on an insertion set 400, or the like. However, inalternative embodiments, the piercing member hub 408 and the connectionbetween the piercing member hub 408 and the insertion set housing, orthe like, is modified to work with the release mechanism of theinsertion device 500.

In preferred embodiments, the release button 508 is biased in positionby a plastic or metal spring. However, in alternative embodiments, therelease button 508 may be manually reset by engaging and disengagingdetents or using other elastomeric materials to bias the release button508 in position relative to the barrel 502 and the carrier body 504. Inpreferred embodiments, pulling up the release button 508 (or extendingit away from the assembly port 503 of the barrel 502) pulls the carrierbody 504 to the retracted position in the barrel 502, where it is lockedin place by triggers 510 and 512 engaging the portal openings 526 and528. This procedure separates the piercing member hub 408 and piercingmember 402 from the housing of the insertion set 400, or the like. Thishas the advantage of removing the piercing member 402 and piercingmember hub 408 to minimize the opportunity of a user being stuck by thepiercing member 402.

FIGS. 40 a-40 g illustrate one method of insertion of an insertion set400 with the insertion device 500 in accordance with an embodiment ofthe present invention. The user first cleans and sterilizes an insertionsite on the skin. Next, the user makes sure the insertion device 500 hasthe carrier body 504 in the advanced position to avoid unintentionalactivation of the insertion device 500 before placement on the skin. Asshown in FIG. 40 a, the user places the insertion set 400 in the cavity514 of the carrier body by aligning the tubing (or wire leads or thelike) with the slot 536 in the carrier body 504 and the slot 538 in thebarrel 502 of the insertion device 500. The user presses against thepiercing member guard 414 (or needle guard) to seat the piercing memberhub 408 (or needle hub) and the insertion set 400 in the cavity 514 ofthe carrier body 504. As shown in FIG. 40 b, the user removes theadhesive backing 416 covering the adhesive 406 on the rim 404 of theinsertion set 400. It is preferred that the piercing member guard 414 isnot removed at this point to avoid unintentional sticks by the piercingmember 402, and minimize or avoid contact with the adhesive 406. Asshown in FIG. 40 c, the user presses against the piercing member guard414 to move the carrier body 504 from the advance position to theretracted position, at which point the trigger buttons 510 and 512 willextend out of the portal openings 526 and 528 to extend beyond the guidechannels 520 and 522 to lock the carrier body 504 in the retractedposition. Next, as shown in FIG. 40 d, the user removes the piercingmember guard 414 (normally by twisting) to expose the piercing member402 while maintaining the insertion set 400 within the carrier body 504.Then, as shown in FIG. 40 e, the user places the surface seat 501 of thebarrel 502 of the insertion device 500 with the insertion set 400 overthe insertion site on the skin. The user depresses the two triggerbuttons 510 and 512 through the portal openings 526 and 528 sufficientlyfor the trigger buttons 510 and 512 to slide down along the guidechannels 520 and 522 to insert and install the insertion set 400 at theinsertion site on the skin. As shown in FIG. 40 f, the user depressesthe release button, 508 to release the insertion set from the cavity 514of the carrier body 504. Finally, as shown in FIG. 40 g, the userremoves the insertion device 500, while maintaining installation of theinsertion set 400. In alternative embodiments, the user may extend therelease button 508 to lift off the piercing member hub 408 and piercingmember 402, and maintain the remainder of the insertion set 400 at theinsertion site on the skin. If the piercing member hub 408 and piercingmember 402 are lifted off the device, the user should re-install thepiercing member guard 414 prior to removal of the remaining set from theinsertion device 500.

FIGS. 41-46 illustrate an insertion device 600 in accordance with athird embodiment that is similar to the insertion devices shown in FIGS.1-34. The insertion device 600 includes a device housing end 601 and acarrier body 602 that has angled insertion contact surfaces 603 and 604.The angled insertion contact surfaces 603 and 604 enable the user toproperly angle the insertion device 600 to insert an insertion set 700,or the like, at the proper insertion angle relative to the skin. Aninsertion set similar to the insertion set 700 is disclosed in U.S.patent application Ser. No. 08/871,831 (PCT Application Serial No.US98/10832) to Van Antwerp et al. entitled “Disposable Sensor InsertionAssembly” or an insertion set that can be inserted at an angle asdisclosed in U.S. patent application Ser. No. 09/034,626 to Funderburket al. entitled “Medication Infusion Set”, both or which are hereinincorporated by reference. Preferred embodiments of the insertion device600 have angled insertion contact surfaces 603 and 604 that permitinsertion of insertion sets, or the like, that are angled from 89.9degrees to 25 degrees relative to the skin surface. In furtherembodiments, the angled insertion contact surfaces 603 and 604 mayhandle even shallower angles down to approximately 10 degrees relativeto the skin surface.

The key is the angled insertion contact surfaces 603 and 604 mirrors theinsertion angle of the insertion set 700, or the like, so that thepiercing member 702 (or needle) of the insertion set 700, or the like,is in axial alignment in the direction of movement of the carrier body602 of the insertion device 600. This permits an insertion devicedesigned primarily for use with a 90 degree insertion set, or the like,to be modified to work with angled insertion sets 700, or the like, bymodification of the angle of the angled insertion contact surfaces 603and 604. In addition, it is preferred that the piercing member 702 ofthe insertion set 700, or the like, be slightly off-center from thecenter axis of the carrier body 602 to permit easy removal of theinsertion device 600 once the insertion set 700, or the like, has beeninserted. Preferred embodiments of the present invention include acarrier body 602 with a receiving structure that includes a recess 606and bore 608 on one side of the carrier body 602. The recess 606 isadapted to hold the piercing member hub 704 by a slight interference fitand the bore 608 is adapted to hold the insertion tubing or transmitterhub 706 of the insertion set 700, or the like. In other embodiments forthe insertion sets such as infusion sets with tubing (or sensor setswith wire leads already connected to a sensor) the bore 608 may be openon one side (not shown) to permit insertion and removal of the infusiontubing (or wire leads), but closed of sufficiently to securely hold andgrasp the insertion tubing or transmitter hub 706 that connects thetubing or wire leads to the housing of the insertion set 700, or thelike.

FIG. 47 illustrates an insertion device 800 that is adapted forinserting insertion sets, or the 15 like, at angles that are generallyless than or equal to 10 degrees relative to the skin surface afterinsertion of the insertion set, or the like. This embodiment includes apair of pinchers 802 and 804 that grasps the skin. The pinchers 802 and804 pinches (or bunches) up the skin in front of a carrier body 806holding an insertion set, or the like. Once the skin is pinched (orbunched up), the user depresses an activation button and the insertionset, or the like, is inserted into the skin. In alternative embodiments,the user presses the pinchers 802 and 804 closer together to activatethe insertion device 800. After insertion, the user releases thepinchers 802 and 804 and removes the insertion device 800 from theinsertion set, or the like. The effect of this embodiment is to raisethe skin so that the actual insertion angle of the piercing memberrelative to the side of the raised (or pinched) area of skin ranges from10 degrees to 90 degrees so that the piercing member is inserted inmanner similar to the embodiments described above. However, when thepinched skin is released, the piercing member is left in the skin at ashallow angle between 0 and 10 degrees. The amount of pinching and theheight of the pinch must be carefully controlled to assure that theinsertion set, or the like, is inserted at the proper depth and locationin the skin tissue. One example of an insertion set that can be insertedat an angle as disclosed in U.S. patent application Ser. No. 09/034,626to Funderburk et al. entitled “Medication Infusion Set”, which is hereinincorporated by reference.

While the description above refers to particular embodiments of thepresent invention, it will be understood that many modifications may bemade without departing from the spirit thereof. The accompanying claimsare intended to cover such modifications as would fall within the truescope and spirit of the present invention.

The presently disclosed embodiments are therefore to be considered inall respects as illustrative and not restrictive, the scope of theinvention being indicated by the appended claims, rather than theforegoing description, and all changes which come within the meaning andrange of equivalency of the claims are therefore intended to be embracedtherein.

1. A low-profile inserter for an angled infusion set having a cannulaassembly including a cannula housing and a cannula extending from thehousing to be inserted subcutaneously, the low-profile insertercomprising: an inserter housing having a bottom wall; a retainerslidably connected to the inserter housing for movement betweenretracted and extended positions in a direction substantially parallelwith the bottom wall, the retainer being adapted to releasably receivethe cannula assembly; a first release member for releasably holding theretainer in the retracted position; a second release member mounted formovement with the retainer for releasably holding the cannula assemblyon the retainer, and a base member connected to the inserter housing,the base member having a lower surface that is adapted to contact anouter skin surface, whereby the cannula can be inserted subcutaneouslyat said acute angle with respect to the skin outer surface; wherein theretainer is removable from the cannula assembly, while maintaininginstallation of the cannula subcutaneously.
 2. A low-profile inserteraccording to claim 1, wherein the lower surface of the base member andthe bottom wall of the inserter housing forming an acute angle.
 3. Alow-profile inserter according to claim 2 and further comprising: abiasing member connected between the retainer and the inserter housingfor biasing the retainer toward the extended position.
 4. A low-profileinserter according to claim 3 further comprising: structure for engagingthe first release member to prevent release of the retainer when in theretracted position; and an operator movably mounted to the inserterhousing, the operator being moveable between a first position formaintaining engagement of the retainer in the retracted position and asecond position for disengaging the retainer to thereby permit releaseof the retainer.
 5. A low-profile inserter according to claim 4 whereinthe operator includes a first end portion exposed through the inserterhousing for manipulation by a user and a second end portion forengagement with the first release member, movement of the operator in afirst direction causing disengagement of the retainer to thereby permitrelease of the retainer.
 6. A low-profile inserter according to claim 5,wherein the operator is biased in a second direction opposite the firstdirection.
 7. A low-profile inserter according to claim 6, wherein theoperator comprises a lower surface that, in the first position, blocksmovement of the operator in the first direction.
 8. A low-profileinserter according to claim 3, further comprising an operator having afirst end portion exposed through the inserter housing for manipulationby a user and a second end portion for engagement with the first releasemember, movement of the operator in a first direction causingdisengagement of the retainer to thereby permit release of the retainer.9. A low-profile inserter according to claim 8, wherein the operator isbiased in a second direction opposite the first direction.
 10. Alow-profile inserter according to claim 2, wherein the acute angle is inthe range of about 10 degrees to about 40 degrees.
 11. A low-profileinserter according to claim 2, wherein the acute angle is approximately30 degrees.
 12. An inserter according to claim 2, wherein the acuteangle is approximately 30 degrees.
 13. A low-profile inserter accordingto claim 1, wherein the lower surface of the base member and the bottomwall of the inserter housing forming approximately a right angle.
 14. Aninserter for a low profile angled infusion set, the inserter comprising:an inserter housing having a bottom wall and a distal end defining anopening therein; a retainer slidably mounted in the inserter housing formovement between retracted and extended positions in a directionsubstantially parallel with the bottom wall, the retainer being adaptedto releasably receive the infusion set, including a cannula and aninsertion needle, the cannula and insertion needle defining an insertionaxis; a tension spring extending between two points for biasing saidretainer toward said extended position; a first release button forreleasing said tension spring; a second release button for releasing theinfusion set from the retainer; and a base member connected to theinserter housing, the base member having a lower surface that is adaptedto contact a user's skin surface, wherein the cannula and the insertionneedle are guided to be inserted subcutaneously along the insertion axiswith respect to the skin surface; wherein the retainer is removable fromthe infusion set, while maintaining installation of the cannulasubcutaneously.
 15. An inserter according to claim 14, wherein the lowersurface of the base member and the bottom wall of the inserter housingforming an acute angle.
 16. An inserter according to claim 15 furthercomprising an operator movably mounted to the inserter housing toprevent inadvertent release of the retainer.
 17. An inserter accordingto claim 16 wherein the operator includes a first end portion exposedthrough the inserter housing for manipulation by a user and a second endportion for engagement with the first release member, movement of theoperator in a first direction causing disengagement of the retainer tothereby permit release of the retainer.
 18. An inserter according toclaim 17, wherein the operator is biased in a second direction oppositethe first direction.
 19. An inserter according to claim 18, wherein theoperator comprises a lower surface that, in the first position, blocksmovement of the operator in the first direction.
 20. An inserteraccording to claim 15, wherein the acute angle is in the range of about10 degrees to about 40 degrees.
 21. An inserter according to claim 14,wherein the lower surface of the base member and the bottom wall of theinserter housing forming approximately a fight angle.
 22. An inserteraccording to claim 21, further comprising an operator having a first endportion exposed through the inserter housing for manipulation by a userand a second end portion for engagement with the first release member,movement of the operator in a first direction causing disengagement ofthe retainer to thereby permit release of the retainer.
 23. An inserteraccording to claim 22, wherein the operator is biased in a seconddirection opposite the first direction.
 24. An inserter according toclaim 14, and further comprising a release member mounted for movementwith the retainer for releasably holding the cannula on the retainer andfor releasing the cannula from the retainer upon operation of the secondrelease button.
 25. An inserter according to claim 24, wherein therelease member comprises a release lever that is pivotally mounted tothe retainer, the release lever including a first end portion exposedfor manipulation by an operator when the retainer is in the extendedposition and a second end portion for engagement with the cannula tothereby hold the cannula on the retainer, whereby pivotal movement ofthe release lever in a first rotational direction causes disengagementof the second end portion and the cannula to thereby release the cannulafrom the inserter.
 26. An inserter for an infusion set, the insertercomprising: an inserter housing defining an opening in a distal endthereof; a retainer slidably connected to the inserter housing formovement between retracted and extended positions, the retainer beingadapted to releasably receive the infusion set including a cannula andan insertion needle, the cannula and the insertion needle defining aninsertion axis; a biasing member connected between the retainer and theinserter housing for biasing the retainer toward the extended position;a first release button for releasing said biasing member; a secondrelease button for releasing the infusion set from the retainer; and abase attached to a lower surface of said inserter housing defining anacute angle with respect to said inserter housing, for guiding theinsertion needle and the cannula to be inserted subcutaneously in skinof a user, along the insertion axis and at an acute angle with respectto the skin; wherein the retainer is removable from the infusion set,while maintaining installation of the cannula subcutaneously.
 27. Aninserter according to claim 26, wherein the first release button issupported for movement in a first direction by a user and is biased in asecond direction opposite the first direction.
 28. A method forinserting an insertion needle and a cannula into skin of a user,comprising the steps of: providing an inserter housing having a bottomwall, a distal end defining an opening therein, and a base memberattached to the bottom wall proximate the distal end, said base memberincluding a lower surface adapted to contact the skin and defining anacute angle with said bottom wall; slidably mounting a retainer withinsaid inserter housing, movable between a retracted position and anextended position, said extended position being substantially parallelwith said bottom wall of said inserter housing; mounting the cannula andthe insertion needle in said retainer to define an insertion axis;providing a tension spring between two points for biasing said retainertoward said extended position, movable between an expanded position anda contracted position; releasing said tension spring by pressing arelease button proximate said distal end of said inserter housing,thereby releasing said spring, whereby said insertion needle and saidcannula are guided to be inserted subcutaneously in the skin at saidacute angle with respect to the skin; depressing a second release buttonto release the cannula and the insertion needle from the retainer; andremoving the inserter while maintaining installation of the cannula andthe insertion needle in the skin of the patient.